
Exactly!! They're not more or less likely to cheat based on sexual orientation and for people who are bi it just means they've picked that person over other men and women, rather that just men or women. They still chose to be with that person so why is there a big deal about not being "trustworthy".

I find it weird because all of the bisexuals I know have been in stable, long term, healthy relationships. It's like saying just because you are attracted to both blonds and brunets you can't be trusted to stick to one person. Lat I checked crap people are crap because of their personality not their sexual orientation.

Had a girl I was interested in and talking to get upset that I was bisexual and, when we talked about me meeting her friends, it was on the condition that I lie and say I was a lesbian so it wouldn’t “turn into a whole thing.” It never got the chance to turn into a “whole thing,” because I ended it there.

If your partner likes blondes and brunettes but dates you (in this fake scenario, let’s say you’re blonde), then would you always be nervous that they’d leave you or cheat on your with a brunette? Who’s to say they wouldn’t cheat on you with ANOTHER blonde?
It has nothing to do with bisexuals. It has to do with shitty people who cheat. Or even just insecure people who can’t trust their partners in a relationship. The whole “they’ll always want the other gender” argument is a stereotype that has been thrown at bisexuals to make them sound “hypersexual” and deviant for a long time from both sides.

I agree with some of your points and in fact made a similar argument above but the fear of your partner going back to the "right" gender is a bit deeper than something flippant like hair color. In an ideal world that comparison would be correct, but in today's day and age, it's quite a lot harder to be gay, so I agree with @207. If I was gay I would also in the beginning be afraid that my partner would go back to the easier gender. Easy to marry, have children, no dirty looks, society considers it to be "right" and "pure". A better comparison might be dating someone with no money. Yes, theres a higher chance someone will leave you than if you were rich, but in the end you dont want someone who's going to leave when the going gets rough. If they leave, that's their flaw and you're better off without them. That's the part that gets me in manga. Yes a bi man has a better chance of choosing a woman than a gay man, but that's a reflection on his character, not the obvious choice everyone will take when given that situation. Nothing in this world is 100%, and you should love your partner and trust them if they give you no reason to believe otherwise.
As a bisexual it really hurt to see "Never Trust a bisexual" in this story and that's why I'm scared to say I'm bi unless it's with my friends